scholarly journals Investigating the inter-annual precipitation changes of Iran

2020 ◽  
Author(s):  
Mokhtar Karami ◽  
Mehdi Asadi
Keyword(s):  
Spatial Autocorrelation ◽  
Annual Precipitation ◽  
Dispersion Index ◽  
Spatial Change ◽  
The Caspian Sea ◽  
Auto Correlation ◽  
Industrial Projects ◽  
Precipitation Anomalies ◽  
Local Moran ◽  
Precipitation Changes

Abstract Precipitation is an important factor in the management of a variety of agricultural and industrial projects. This study investigated the temporal-spatial change of inter-annual precipitation of Iran from 1977 to 2007 by using the APHRODITE precipitation database. Statistical methods were applied, such as spatial auto-correlation, Global Moran's index, Local Moran's I index, and hotspots to acquire the variations in precipitation. The highest spatial anomalies belong to September (75.26) and October (45.02), based on the Dispersion index. Also, the size of the largest cluster of Iran's precipitation clusters is developed during winter, cited by the index's outputs, which indicates the relative regularity of Iran's precipitation. The results of the spatial statistics showed that inter-annual precipitation changes in Iran have an upward cluster model. The results of the Global Moran statistics showed that September, with the lowest number (0.712114), has the highest spatial precipitation anomalies throughout the year in Iran. Meanwhile, precipitation has a positive spatial autocorrelation on the Caspian Sea shores and western and south-western parts of the country (mainly Zagros highlands) and a negative spatial autocorrelation in parts of the central and south-eastern areas based on the Local Moran index and hotspots.

Analysis of precipitation changes and its possible reasons in Songhua River Basin of China

2019 ◽  
Vol 11 (3) ◽  
pp. 839-864 ◽  
Author(s):  
Tianxiao Li ◽  
Zhaoqiang Zhou ◽  
Qiang Fu ◽  
Dong Liu ◽  
Mo Li ◽  
...  
Keyword(s):  
River Basin ◽  
Time Scale ◽  
Great Influence ◽  
Precipitation Change ◽  
Annual Precipitation ◽  
Human Beings ◽  
Songhua River ◽  
Songhua River Basin ◽  
Change Characteristics ◽  
Precipitation Changes

Abstract Changes in precipitation have a great influence on human beings. The study of precipitation can aid in understanding regional climate change characteristics and the hydrological cycle. Therefore, in this study, the standardized precipitation index is combined with a simple linear regression test, Mann–Kendall trend analysis, Sen's slope method, principal component analysis and partial correlation analysis to study precipitation and drought distributions in the Songhua River Basin and the causes of precipitation changes in this area. The results are as follows: (1) The average annual precipitation change in this area is not significant, but there are significant differences in seasonal precipitation changes. (2) On a long-term time scale, this area presents a wet trend from southeast to northwest. On a short-term time scale, spring and winter show a wet trend. Winter has changed significantly. Summer and autumn show a dry trend. (3) The average annual and rainy season (RS) precipitation shows step change characteristics. Precipitation change in RS is the main reason for annual precipitation change. (4) The Asian meridional circulation/zonal index have significant effects on precipitation and dry/wet changes in this area. The western Pacific subtropical high and the East Asian summer monsoon are also important factors in this area.

scholarly journals Determinants of homicides in the state of Bahia, Brazil, in 2009

2014 ◽  
Vol 17 (1) ◽  
pp. 135-146 ◽  
Author(s):  
Carlos Augusto Moreira de Sousa ◽  
Cosme Marcelo Furtado Passos da Silva ◽  
Edinilsa Ramos de Souza
Keyword(s):  
Spatial Autocorrelation ◽  
The State ◽  
Metropolitan Region ◽  
Economic Research ◽  
Inverse Association ◽  
Homicide Rates ◽  
Parallel Increase ◽  
Bolsa Familia ◽  
Local Moran ◽  
Socioeconomic And Demographic Factors

PURPOSE: To carry out a study of association between socioeconomic and demographic factors and homicides in general population, in the state of Bahia, in 2009. METHODS: This is an ecological study. The data were collected from the database of the Information System about Mortality of the Ministry of Health, from the Brazilian Institute of Geography and Statistics and the Institute of Applied Economic Research. The Global Moran index was calculated for the detection of spatial autocorrelation, and the Local Moran index was calculated for the detection of spatial Clusters. The transformation in the variable answer (homicides rates) was performed and it was shaped using the Conditional Autoregressive Model. RESULTS: The data showed spatial autocorrelation. Two clusters of municipalities with high rates of homicides were identified, one located predominantly in the Greater Metropolitan Region of Salvador and the other in the South Region of Bahia, especially Eunápolis and Lauro de Freitas, which had the highest rates. The Average Residents Variables, local GDP and the Percentage of Illiteracy presented an inverse association with homicide rates, and the variables Firjan's municipal development index of work and income. Enrolment in high school and the Average of Bolsa Família were directly associated. CONCLUSIONS: The urbanization process, in most cases, not controlled by the State, in most cases, made the cities bigger and with better socioeconomic conditions, attraction centers for people with different socioeconomic levels, increasing the social inequality among the residents of these regions, with parallel increase in homicide rates.

scholarly journals Western U.S. lake expansions during Heinrich stadials linked to Pacific Hadley circulation

2018 ◽  
Vol 4 (11) ◽  
pp. eaav0118 ◽  
Author(s):  
D. McGee ◽  
E. Moreno-Chamarro ◽  
J. Marshall ◽  
E. D. Galbraith
Keyword(s):  
United States ◽  
Hadley Circulation ◽  
Winter Precipitation ◽  
Aleutian Low ◽  
Central Pacific ◽  
Subtropical Jet ◽  
Precipitation Anomalies ◽  
Hemisphere Winter ◽  
Atmospheric Changes ◽  
Precipitation Changes

Lake and cave records show that winter precipitation in the southwestern United States increased substantially during millennial-scale periods of Northern Hemisphere winter cooling known as Heinrich stadials. However, previous work has not produced a clear picture of the atmospheric circulation changes driving these precipitation increases. Here, we combine data with model simulations to show that maximum winter precipitation anomalies were related to an intensified subtropical jet and a deepened, southeastward-shifted Aleutian Low, which together increased atmospheric river–like transport of subtropical moisture into the western United States. The jet and Aleutian Low changes are tied to the southward displacement of the intertropical convergence zone and the accompanying intensification of the Hadley circulation in the central Pacific. These results refine our understanding of atmospheric changes accompanying Heinrich stadials and highlight the need for accurate representations of tropical-extratropical teleconnections in simulations of past and future precipitation changes in the region.

Assessment of bioclimatic comfort conditions based on Physiologically Equivalent Temperature (PET) using the RayMan Model in Iran

2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Mohammad Daneshvar ◽  
Ali Bagherzadeh ◽  
Taghi Tavousi
Keyword(s):  
Thermal Comfort ◽  
Physiological Stress ◽  
Coastal Areas ◽  
Physiologically Equivalent Temperature ◽  
Annual Precipitation ◽  
Equivalent Temperature ◽  
The Caspian Sea ◽  
Bioclimatic Comfort ◽  
The Persian Gulf ◽  
Rayman Model

AbstractIn this study thermal comfort conditions are analyzed to determine possible thermal perceptions during different months in Iran through the Physiologically Equivalent Temperature (PET). The monthly PET values produced using the RayMan Model ranged from −7.6°C to 46.8°C. Over the winter months the thermal comfort condition (18–23°C) were concentrated in southern coastal areas along the Persian Gulf and Oman Sea. Most of the country experienced comfort conditions during the spring months, in particular in April, while during the summer months of July and August no thermal comfort conditions were observed. In November coastal areas of the Caspian Sea had the same physiological stress level of thermal comfort as April. The map produced showing mean annual PET conditions demonstrated the greatest spatial distribution of comfortable levels in the elevation range from 1000 to 2000 meter a.s.l., with annual temperatures of 12–20°C and annual precipitation of under 200 mm. The statistical relationship between PET conditions and each controlling parameter revealed a significant correlation in areas above 2000 meter, annual temperature over 20°C and annual precipitation of 200–400 mm with a correlation coefficient (R 2) of 0.91, 0.97 and 0.96, respectively.

scholarly journals Observed and Projected Changes in Temperature and Precipitation in the Core Crop Region of the Humid Pampa, Argentina

Climate ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 40
Author(s):  
Gabriela V. Müller ◽  
Miguel A. Lovino ◽  
Leandro C. Sgroi
Keyword(s):  
Climate Extremes ◽  
Annual Precipitation ◽  
Climate Conditions ◽  
The Core ◽  
Temperature And Precipitation ◽  
Mean Temperature ◽  
Maximum Temperatures ◽  
Projected Changes ◽  
Precipitation Changes ◽  
Precipitation Events

The core crop region of the Humid Pampa is one of the most productive agricultural lands around the world and depends highly on climate conditions. This study assesses climate variability, climate extremes, and observed and projected climate changes there, using 1911–2019 observations and CMIP5 model simulations. Since 1970, the annual mean temperature has risen by 1 °C and the mean annual minimum and maximum temperatures by 2 and 0.5 °C, respectively. The frequency of warm days and nights increased, and cold days and nights decreased. Heatwaves became longer and more intense, and cold waves decreased with less frost events. Annual precipitation increased by 10% from 1911, mainly in summer, and years with excess precipitation outnumbered those with a deficit. Both intense precipitation events and consecutive dry days grew, suggesting more annual precipitation falling on fewer days. Projections show a warming of 1 °C by 2035, regardless of the scenario. From then on until 2100, mean temperature will increase by 2 and 3–3.5 °C in the RCP4.5 and RCP8.5 scenarios, respectively. Annual precipitation will grow 8 and 16% from current values by 2100 in the RCP4.5 and RCP8.5 scenarios, respectively. No major precipitation changes are projected in the RCP2.6 scenario.

scholarly journals Inter-hemispheric synchroneity of Holocene precipitation anomalies controlled by Earth’s latitudinal insolation gradients

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Michael Deininger ◽  
Frank McDermott ◽  
Francisco W. Cruz ◽  
Juan Pablo Bernal ◽  
Manfred Mudelsee ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Energy Transport ◽  
Temperature Gradients ◽  
South American ◽  
Latitudinal Distribution ◽  
Arctic Amplification ◽  
Precipitation Anomalies ◽  
Earth’S Climate ◽  
Precipitation Changes ◽  
Northern And Southern Hemispheres

Abstract Atmospheric circulation is a fundamental component of Earth’s climate system, transporting energy poleward to partially offset the latitudinal imbalance in insolation. Changes in the latitudinal distribution of insolation thus force variations in atmospheric circulation, in turn altering regional hydroclimates. Here we demonstrate that regional hydroclimates controlled by the Northern Hemisphere mid-latitude storm tracks and the African and South American Monsoons changed synchronously during the last 10 kyrs. We argue that these regional hydroclimate variations are connected and reflect the adjustment of the atmospheric poleward energy transport to the evolving differential heating of the Northern and Southern Hemispheres. These results indicate that changes in latitudinal insolation gradients and associated variations in latitudinal temperature gradients exert important control on atmospheric circulation and regional hydroclimates. Since the current episode of global warming strongly affects latitudinal temperature gradients through Arctic amplification, our results can inform projections of likely inter-hemispheric precipitation changes in the future.

scholarly journals Influence of three phases of El Niño–Southern Oscillation on daily precipitation regimes in China

2019 ◽  
Vol 23 (2) ◽  
pp. 883-896 ◽  
Author(s):  
Aifeng Lv ◽  
Bo Qu ◽  
Shaofeng Jia ◽  
Wenbin Zhu
Keyword(s):  
El Niño ◽  
Daily Precipitation ◽  
El Nino ◽  
Southern Oscillation ◽  
Annual Precipitation ◽  
Rainfall Events ◽  
Enso Events ◽  
Precipitation Regimes ◽  
Precipitation Anomalies ◽  
Three Phases

Abstract. In this study, the impacts of the El Niño–Southern Oscillation (ENSO) on daily precipitation regimes in China are examined using data from 713 meteorological stations from 1960 to 2013. We discuss the annual precipitation, frequency and intensity of rainfall events, and precipitation extremes for three phases (eastern Pacific El Niño – EP, Central Pacific El Niño – CP, and La Niña – LN) of ENSO events in both ENSO developing and ENSO decaying years. A Mann–Whitney U test was applied to assess the significance of precipitation anomalies due to ENSO. Results indicated that the three phases each had a different impact on daily precipitation in China and that the impacts in ENSO developing and decaying years were significantly different. EP phases caused less precipitation in developing years but more precipitation in decaying years; LN phases caused a reverse pattern. The precipitation anomalies during CP phases were significantly different than those during EP phases, and a clear pattern was found in decaying years across China, with positive anomalies over northern China and negative anomalies over southern China. Further analysis revealed that anomalies in frequency and intensity of rainfall accounted for these anomalies in annual precipitation; in EP developing years, negative anomalies in both frequency and intensity of rainfall events resulted in less annual precipitation, while in CP decaying years, negative anomalies in either frequency or intensity typically resulted in reduced annual precipitation. ENSO events tended to trigger extreme precipitation events. In EP and CP decaying years and in LN developing years, the number of very wet day precipitation (R95 p), the maximum rainfall in 1 day (Rx1d), and the number of consecutive wet days (CWD) all increased, suggesting an increased risk of flooding. On the other hand, more dry spells (DSs) occurred in EP developing years, suggesting an increased likelihood of droughts during this phase. Possible mechanisms responsible for these rainfall anomalies are speculated to be the summer monsoon and tropical cyclone anomalies in ENSO developing and decaying years.

scholarly journals Efek Limpahan Pertumbuhan Antar-Kabupaten/Kota di Provinsi Jawa Timur Tahun 2001–2013

2015 ◽  
Vol 16 (1) ◽  
pp. 31-46
Author(s):  
Pristiawan Wibisono ◽  
Mudrajad Kuncoro
Keyword(s):  
Spatial Autocorrelation ◽  
Central Region ◽  
Spatial Interaction ◽  
Spatial Association ◽  
Spillover Effects ◽  
Fast Growing ◽  
Growth Pole ◽  
Analysis Tools ◽  
Local Moran ◽  
Growing Region

Growth Spillover Effects Among Districts/Municipalities in East Java Province, 2001–2013This study aims to identify the typology of districts/municipalities in East Java Province, and analyze the growth spillover effects among districts/municipalities. This study was conducted using analysis tools such as Klaassen Typology, identification of growth pole based on the definition proposed by Richardson, the calculation of growth spillover effects and detection of spatial autocorrelation with local indexes Moran and Local Indicators of spatial Association (LISA). The results from this study is that advanced and fast-growing districts/municipalities from 2001 until 2013 concentrated in the central region of East Java Province. Consistency as advanced and fast-growing region is an indicator of growth poles, shown by Surabaya.Keywords: Districts/Municipalities Typology; Growth Pole; Spillover Eects; Spatial Interaction; Local Moran Index and LISA AbstrakPenelitian ini bertujuan untuk mengidentifikasi tipologi kabupaten/kota di Provinsi Jawa Timur dan menganalisis efek limpahan pertumbuhan antar-kabupaten/kota. Alat analisis yang dipergunakan adalah Tipologi Klaassen, identifikasi kutub pertumbuhan berdasarkan definisi yang dikemukakan oleh Richardson, perhitungan efek limpahan pertumbuhan, serta deteksi autokorelasi spasial dengan indeks lokal Moran dan Local Indicators of Spatial Association (LISA). Hasil penelitian ini menunjukkan bahwa kabupaten/kota yang tergolong maju dan cepat tumbuh pada tahun 2001 hingga 2013 terpusat di kawasan tengah Provinsi Jawa Timur. Konsistensi sebagai daerah cepat tumbuh dan maju/kaya yang merupakan indikator kutub pertumbuhan, ditunjukkan oleh Kota Surabaya.

scholarly journals Measurement of spatial equity : a case study of nursing institution

2019 ◽  
Author(s):  
Xin Sui ◽  
◽  
Yifan Yu ◽  
Liu Huhui ◽  
◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Spatial Autocorrelation ◽  
Supply And Demand ◽  
The Elderly ◽  
Spatial Dimension ◽  
Spatial Equity ◽  
Public Resources ◽  
Local Moran ◽  
The Impact

Equity and justice have always been important norms in the field of urban planning. With the gradual deepening of understanding of residential environment, the research context of equity and justice related to location is becoming more and more sophisticated. Recently, varieties of subjects Including Public Health and Geography focus on the inequity of public resources in spatial distribution and how to measure the degree of this gap. In general, the mainstream measurement methods can be summarized into two categories: (1) The description of phenomenon caused by the spatial inequities, and accessibility is a typical method of this type. (2) the direct quantification of inequity, such as Gink Coefficient which is originated from the economics field and introduced into the measurement of health equity, and Getis-Ord General G, together with Moran’ index is the most commonly method used into the general spatial autocorrelation. In this paper, based on the overall literature review of the concept of equity in the study using these methods and a summary of their specific context of the measurement using, nursing institution in Shanghai, China are regarded as a typical case to practice these methods and compare the differences in using. Meantime, the impact of the politics and planning related to this special facility is also been considered. Results show that, accessibility of nursing institution among elderly groups is much different under different research distance, and the overall trend seems like the research units in suburb appears higher accessibility than those in highly urbanized area. And Gink Coefficient helps us determine the proportion of the elderly population in different reachable areas in Shanghai is within a reasonable range. However, Global Moran’ index provide reliable evidence that the existence of the aggregation combined by the high-value units. It indicates that there are inequities among the distribution of aged-nursing resources, and Local Moran I （LISA）help us to find the specific boundaries of these areas. In general, in the study of the equity related to location, accessibility can only reflect the differences phenomenon in distribution, but it is not clear to describe this gap to what extent, and it’s difficult to achieve the possibility of comparison among different periods and different subjects. The Gini coefficient often focuses on the unfairness of the distribution of people, but ignored the aggregation characteristics of the spatial dimension, which the analysis of spatial autocorrelation can make up. All these methods proved that it’s necessary to consider both the spatial distribution of supply and demand. And the discussion about equity related to location should be strictly qualified in study.

scholarly journals Influence of three phases of El Niño-Southern Oscillation on daily precipitation regimes in China

2018 ◽  
Author(s):  
Aifeng Lv ◽  
Bo Qu ◽  
Shaofeng Jia ◽  
Wenbin Zhu
Keyword(s):  
El Niño ◽  
Daily Precipitation ◽  
El Nino ◽  
Southern Oscillation ◽  
Annual Precipitation ◽  
Rainfall Events ◽  
Enso Events ◽  
Precipitation Regimes ◽  
Precipitation Anomalies ◽  
Three Phases

Abstract. In this study, the impacts of the El Niño-Southern Oscillation (ENSO) on daily precipitation regimes in China are examined using data from 713 meteorological stations from 1960 to 2013. We discuss the annual precipitation, frequency and intensity of rainfall events, and precipitation extremes for three phases (Eastern Pacific El Niño (EP), Central Pacific El Niño (CP), and La Niña (LN)) of ENSO events in both ENSO developing and ENSO decaying years. A Mann–Whitney U test was applied to assess the significance of precipitation anomalies due to ENSO. Results indicated that the three phases each had a different impact on daily precipitation in China and that the impacts in ENSO developing and decaying years were significantly different. EP phases caused less precipitation in developing years but more precipitation in decaying years; LN phases caused a reverse pattern. The precipitation anomalies during CP phases were significantly different than those during EP phases and a clear pattern was found in decaying years across China, with positive anomalies over northern China and negative anomalies over southern China. ENSO events which altered the frequency and intensity of rainfall roughly paralleled anomalies in annual precipitation; in EP developing years, negative anomalies in both frequency and intensity of rainfall events resulted in less annual precipitation while in CP decaying years, negative anomalies in either frequency or intensity typically resulted in reduced annual precipitation. ENSO events triggered more extreme precipitation events. In EP and CP decaying years and in LN developing years, the number of very wet days (R95p), the maximum rainfall in one day (Rx1d), and the number of consecutive wet days (CWD) all increased, suggesting an increased risk of flooding. In addition, more dry spells (DS) occurred in EP developing years, suggesting an increased likelihood of droughts during this phase.

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